Friday, July 23, 2010
By Dennis Thompson
Friday, July 23, 2010
FRIDAY, July 23 (HealthDay News) -- People concerned about rightfully fret about their cholesterol, blood pressure and blood sugar levels, but there's another overarching problem that could eclipse all those risk factors.
plays a role in almost all the coronary risk factors," said Dr. Vincent
Bufalino, president and chief executive of Midwest Heart Specialists, medical
Obesity can boost your levels of bad cholesterol, raise your blood pressure and increase your chances of acquiring diabetes, Bufalino said. In other words, obesity ties directly into the three biggest .
Rising obesity rates also threaten to undermine progress that has been made in controlling those risk factors.
A study presented at the American Heart Association's annual meeting reported that blood pressure and blood sugar levels continue to rise in adults, mainly fueled by increases in obesity. Those increases are such that they overwhelm improving heart-health trends, such as a drop in "bad" cholesterol levels and lower smoking rates.
given the , experts believe that things will only get
worse. One of every three children and teens in the
problem exists that the world is getting more and more obese," said Dr.
Gerald Fletcher, a cardiovascular physician with the Mayo Clinic in
The definition of obesity and overweight depends on body mass index, or BMI, an estimate of a person's body fat. People with a BMI of 30 to 39.9 are considered obese, according to the U.S. National Institutes of Health, and those with a BMI of 25 to 29.9 are considered overweight. A BMI of 40 or more indicates morbid obesity.
Doctors know that obesity plays a role in the three big risk factors, based on extensive research, but Bufalino said there's common-sense proof available, too. People who lose weight and keep it off, he points out, always see across-the-board improvements in those risk factors.
"In all three categories -- cholesterol, blood pressure and blood glucose -- sustained weight loss will improve those numbers," Bufalino said.
People who lose weight experience a decrease in their high blood pressure, and their levels of "bad" cholesterol (, or low-density lipoprotein) drop, according to the American Heart Association. They also tend to experience an increase in "good" cholesterol (HDL, or high-density lipoprotein), which lowers risk for by helping clear the blood vessels of bad cholesterol.
Losing weight also is considered one of the best ways to bring diabetes under control, or to avoid it altogether if a person has high blood sugar levels that indicate pre-diabetes.
People become obese by taking in more calories than they can burn off over the course of a day, according to the American Heart Association. They compound the problem by eating foods rich in fat, which contain more than twice the calories gram-for-gram of either protein or carbohydrates, and by eating foods loaded with sugar, which provides "empty" calories that have no nutritional value but drastically affect the body's blood glucose levels.
"People take care of their cars: They change the oil, they buy new tires," Fletcher said. "But there's only one body, and if we don't take care of it, we can't expect the health-care system to do it for us. You can buy another car, but you can't buy another body."
The answer, then, is a simple one: To reduce the chances that you'll develop heart disease, you need to control your calorie intake and exercise regularly.
A healthy diet involves watching everything you eat and counting the calories, Bufalino and Fletcher said. General tips include:
Dieting can help you lose weight, but you also need to exercise. "Reducing your calorie intake is what gets it started, and exercise provides the maintenance that keeps the weight off," Bufalino said.
NIH experts recommend that people who are out of shape start off slowly, performing moderate exercise -- walking for a half-hour three times a week, for instance -- and then build up from there.
Healthy weight loss is gradual, about one or two pounds a week, according to the CDC. Keep in mind that one pound equals about 3,500 calories, so to lose that pound in a week, each day you have to burn 500 more calories than you take in.
Bufalino said he encourages people to lose 10 pounds in six months, which is an attainable goal that keeps them from becoming frustrated. They then can build on their success.
"If you can get a 10 percent weight loss, that's a successful effort to control your weight problem," he said. For example, someone who is 220 pounds should try to ultimately lose 22 pounds if they want to see their heart-healthy numbers improve.
For more on life-saving weight loss, read about one woman's story.
Friday, July 23, 2010
ScienceDaily (July 23, 2010) — German researchers have isolated a strain of Salmonella in pork that is closely related to the bacteria commonly found in chickens and linked to human food-borne illness. They report their findings in the July 2010 issue of the journal Applied and Environmental Microbiology.
First emerging overseas in the mid-1990's in pigs, initial studies showed the genetic make-up of Salmonella enterica subsp. enterica serovar Typhimurium (or S. enterica serovar 4,,12:i:-) to be very similar to S. enterica serovar Typhimurium, the strain commonly found in chickens. It is a known cause of gastroenteritis and has become increasingly associated with worldwide outbreaks over the last few years.
"Interestingly, the number of S. enterica serovar 4, ,12:i:- strains isolated from humans and sent on voluntary basis to the National Reference Centre for Salmonella and other Enterics increased from 0.1% in 1999 to 14.0% in 2008," say the researchers.
In the study researchers collected and analyzed strains of S. enterica serovar 4,,12:i:-from pigs, pork, and humans over a two-year period in an attempt to better understand its transmission capabilities. Additionally, the strains' genetic relatedness, pathogenicity and antimicrobial resistance were compared to that of S. enterica serovar Typhimurium. Two major clonal lineages were observed among the two strains and 65% of isolates from both lineages were resistant to ampicillin, streptomycin, tetracycline and sulfamethoxazole.
"Overall the study indicates that in
E. Hauser, E. Tietze, R. Helmuth, E. Junker, K. Blank, R. Prager, W. Rabsch, B. Appel, A. Fruth, B. Malorny. Pork Contaminated with Salmonella enterica Serovar 4,,12:i:-, an Emerging Health Risk for Humans. Applied and Environmental Microbiology, 2010; 76 (14): 4601 DOI: 10.1128/AEM.02991-09
By Anne Harding
Friday, July 23, 2010
may be non-optional for pregnant women to have high consumption of these types
of products," Dr. Thorhallur I. Halldorsson of the Statens Serum Institut
"Diet" drinks are widely promoted as a healthy alternative to sugary sodas and juices, but Halldorsson and his colleagues note that there's been little research on the safety of regular consumption of artificial sweeteners in humans.
-- both artificially sweetened and sugar sweetened -- were recently linked to high blood pressure, the researchers add, which increases the risk of premature delivery. To investigate whether there might be a direct link, the researchers looked at nearly 60,000 Danish women who reported on their diet, including how many soft drinks they had each day, at around 25 weeks of pregnancy.
Around 5 percent of women delivered their babies before 37 weeks.
Women who had at least one serving of artificially sweetened soda a day while they were pregnant were 38 percent more likely to deliver preterm than women who drank no diet soda at all, the researchers report in the .
Women who had at least four diet sodas a day were nearly 80 percent more likely to deliver preterm. The association was the same for normal-weight and overweight women.
The researchers did not report the actual risk of premature babies in each group. However, according to the March of Dimes, one in eight babies -- or around 13 percent -- is born too soon. This means that if drinking does indeed increase risk - which must first be confirmed by other research teams -- a woman who drank at least one diet soda daily would have a 17 percent risk, while her risk would be around 22 percent if she drank four or more diet sodas.
In a statement, the Calorie Control Council, a lobbying group for companies that make and distribute low-calorie foods, called the study "misleading."
"This study may unduly alarm pregnant women. While this study is counter to the weight of the scientific evidence demonstrating that low-calorie sweeteners are safe for use in pregnancy, research has shown that overweight and obesity can negatively affect pregnancy outcomes," Beth Hubrich, a dietitian with the council, said in the statement. "Further, low-calorie sweeteners can help pregnant women enjoy the taste of sweets without excess calories, leaving room for nutritious foods and beverages without - something that has been shown to be harmful to both the mother and developing baby."
Because only diet soda was linked to preterm delivery, not sugar-sweetened soda, the findings suggest that the artificial sweetener itself, not soda drinking, could account for the relationship, the researchers say. However, they add, other possible causes for the link can't be ruled out.
The researchers didn't look at specific artificial sweeteners, and Halldorsson noted that many beverages contain more than one of these chemicals. However, he and his colleagues say, there is indirect evidence linking the sweetener aspartame to preterm delivery in animals.
Aspartame breaks down into methanol and other substances in the body, which can in turn be converted to toxic substances such as formaldehyde and formic acid, the researchers explain. And studies in non-human primates have linked even very low exposure to methanol to shortened pregnancy and labor complications.
While pregnant women who consume soft drinks shouldn't be alarmed by the findings, Halldorsson said, "what we are seeing warrants further attention."
Friday, July 23, 2010
ScienceDaily (July 23, 2010) — Eighty years ago, the medical establishment believed cancer was caused by a dysfunction of metabolism, but the idea went out of vogue. Now, scientists are again looking at metabolism and its role in cancer and other common diseases. Metabolism is a highly connected network of reactions that are arranged in parallel and interacting pathways. Such parallelism can mask how genes are linked with disease traits and make it difficult to treat conditions.
In a paper in the journal Chaos, published by the
American Institute of Physics, researchers at
The research suggests that the many pathways in the human metabolic network buffer each other to a striking degree, inducing "deep" epistasis -- the suppression of a mutation by one or more seemingly unrelated genes. Their results identify specific in vivo perturbation experiments that could confirm this deep parallelism in human metabolic pathways.
"The results of our analysis could also be used to statistically probe complex relationships between genetic variation and disease," says co-author Marcin Imielinski.
Marcin Imielinski, Calin Belta. Deep epistasis in human metabolism. Chaos: An Interdisciplinary Journal of Nonlinear Science, 2010; 20 (2): 026104 DOI: 10.1063/1.3456056
Thursday, July 22, 2010
Thursday, July 22, 2010
THURSDAY, July 22 (HealthDay News) -- A new animal study offers the first direct bit of evidence that ozone, a major component of smog, may trigger the death of heart cells.
In small early tests with rats, found that exposure to ground-level ozone over several weeks boosted the activity of tumor necrosis factor-alpha (TNF-A), an indication of inflammation. Increased TNF-A levels have been linked to a drop in levels of a heart-protective protein called Caveolin-1 (Cav1). This protein is believed to protect the heart by binding to a chemical called p38MAPK alpha, which is a known cell death signaling chemical.
Levels of the heart-protective Cav1 protein decreased in the hearts of rats exposed to ozone compared to the hearts of rats who breathed filtered air.
"We believe the decreased levels of Cav1 make more unbound p38MAPK alpha available for telling the to die. That link between Cav1 and (ozone) has never been shown in the heart," Rajat Sethi, an assistant professor in the pharmaceutical sciences department at Texas A&M Health Science Center's college of pharmacy, said in an American Heart Association news release.
study was to be presented Wednesday at an American Heart Association meeting in
"Several studies have already shown that air pollution increases the risk of coronary arteriosclerosis and . Post-menopausal women have been shown to have an increased risk of stroke as well from fine particulate matter in air pollution," Dr. Len Horovitz, a pulmonary specialist at Lenox Hill Hospital in New York City, said in a news release.
"Now there is evidence (in rats) that ozone, a key component among others in smog, can trigger a direct effect on cardiac tissue through a cascade of inflammatory mediators. The endpoint in this domino effect can result in death of heart cells -- a heart attack, in essence," he said.
The researchers cautioned, however, that more evidence was needed before human studies can begin.
The U.S. National Institute of Environmental Health Sciences has more about air pollution and cardiovascular health.
By Amy Norton
Thursday, July 22, 2010
The findings, reported in the journal Diabetes, support the theory that nutrition and growth during fetal development may affect the odds of developing type 2 diabetes later in life.
studies, for example, have found a relationship between and higher diabetes risk in adulthood in both
developed and developing countries, said Dr. Frank B. Hu, of the Harvard School
of Public Health in
Adults born at a low weight have also been found to have higher risks of heart and kidney disease than those born within the normal range.
These latest findings, Hu told Reuters Health in an email, give further support to the "developmental origins" hypothesis. According to that theory, poor nutrition during pregnancy may alter fetal development in a way that affects lifelong metabolism and disease risks.
For example, Hu noted, animal research suggests that poor fetal nutrition may affect the structure and function of cells in the pancreas that produce insulin, the hormone that regulates blood sugar.
In humans, problems in the body's response to insulin precede the development of type 2 diabetes.
For their study, Hu and his colleagues looked at among 7,874 Chinese adults born between 1954 and 1964. Those born between October 1, 1959 and September 30, 1961 were considered to have been exposed to the nation's famine during . Those born earlier were categorized as exposed during early-, mid- or late-childhood; those born later were considered "unexposed."
Overall, roughly 6 percent of the fetal-exposed group had hyperglycemia -- blood sugar that was abnormally high but not yet high enough for a diagnosis of type 2 diabetes. That compared with just over 2 percent of the group unexposed to the famine.
exposed to the famine during late-childhood also had a 6-percent rate of
hyperglycemia. But when the researchers considered other factors - such as
study participants' age, exercise levels and smoking habits -- they found that
fetal exposure to the famine, especially in the regions of
Of fetal-exposed adults from the most severely affected areas, just over 7 percent had hyperglycemia, versus 2 percent of the unexposed group, and anywhere from 2 percent to 5 percent of those exposed during childhood.
With other factors taken into account, adults in the group exposed during fetal development were four times more likely than their unexposed counterparts to have hyperglycemia.
What's more, the researchers found a particularly strong link between fetal exposure to the famine and hyperglycemia among adults who currently had an "affluent" Western-style diet rather than a traditional Chinese diet. This group had the highest prevalence of hyperglycemia, at 19 percent.
According to Hu, this suggests that a "rich" diet later in life may worsen any effects of fetal undernourishment on the long-term risk of hyperglycemia.
The researchers found no clear association, however, between famine exposure of any kind and the risk of type 2 diabetes in adulthood. But that, they say, may be because there too few diabetes cases; at the time of the study, those in the fetal-exposed group were in their early 40s, and type 2 diabetes is most common after the age of 45.
None of the findings prove that fetal nutrition, itself, affects the long-term risk of hyperglycemia -- or, by extension, type 2 diabetes. But they add to evidence of an association between nutrition in the womb and adult disease risks, according to the researchers.
The bottom line, Hu said, is that adequate nutrition during pregnancy is "critical" for both mom and baby.
According to the of Obstetricians and Gynecologists (ACOG), normal-weight women should get, on average, an extra 300 calories per day during pregnancy, and gain about 25 to 35 pounds by the end. Overweight and obese women should be more careful about their calories since their weight-gain recommendations are lower: 15 to 25 pounds for overweight women, and 11 to 20 pounds for those who are obese.
All pregnant women, according to ACOG, should eat a well-balanced diet and, in most cases, use prenatal vitamins to ensure that they are getting enough nutrients. During pregnancy, women need extra amounts of certain nutrients, like iron, folic acid and vitamins B6 and B12.
Diabetes, online July 9, 2010.
Thursday, July 22, 2010
THURSDAY, July 22 (HealthDay News) -- The risk of placental separation during labor is three times higher than normal in pregnant women with antibodies that indicate early thyroid disease, a new study has found.
the findings don't suggest that routinely screening pregnant women for thyroid
problems or providing them with thyroid supplementation would offer any
benefit, according to the researchers at the University of Texas Southwestern
Medical Center in
Thyroid peroxidase (TPO) is an enzyme that incorporates iodine into . In some autoimmune diseases, the body creates antibodies against TPO. This leads to lower TPO levels and slower body metabolism. But when antibody levels are low, the thyroid may be able to compensate and produce normal amounts of thyroid hormones, the study authors explained in a news release from UT Southwestern Medical Center.
In the new study, the researchers analyzed levels of anti-TPO antibodies from 17,298 women before they reached 20 weeks of pregnancy and compared those levels with the mothers' and babies' health after birth.
Nearly 6 percent of the women had anti-TPO antibodies, but the rate varied according to ethnicity -- 8.4 percent for whites, 6.1 percent for Hispanics and 2.6 percent for black women. The women with anti-TPO antibodies had normal levels of thyroid hormones, the study authors noted.
Rates of birth complications were the same for women with anti-TPO antibodies and those without the antibodies, with the exception of placental abruption. This is a rare but potentially fatal situation in which the placenta separates from the uterus too early. Placental abruption occurred in 1 percent of antibody-positive women and in 0.3 percent of antibody-negative women, the investigators found.
A mother's antibody status had no effect on the health of her baby, the authors noted.
"Our work shows a link between anti-TPO antibodies and placental abruption, but that does not necessarily mean that thyroid supplementation would improve the health of the women or babies," co-lead study author Dr. Brian Casey, a professor of obstetrics and gynecology, said in the news release.
The study is published in the August issue of Obstetrics & Gynecology.
The March of Dimes has more about placental abruptions.
By Amy Norton
Thursday, July 22, 2010
Whether a fishy diet itself is the reason for the benefit is not clear from the findings.
Clinical trials have shown, for instance, that omega-3s can lower triglycerides (a type of blood fat), and a prescription medication containing the fats -- sold as Lovaza -- is sometimes used to treat very high triglyceride levels.
The new study, of 3,500 Korean adults ages 40 to 69, found that men who had a serving of fish each day were 57 percent less likely than those who dined on fish less than once per week to develop metabolic syndrome over three years.
Metabolic syndrome refers to a collection of risk factors for diabetes, heart disease and stroke -- including abdominal obesity, , high blood sugar, low HDL cholesterol and high triglycerides. The syndrome is typically diagnosed when a person has three or more of those traits, and the National Health and Nutrition Examination Survey, a major study, found that it can double the risk of .
research had linked higher fish intake to a lower risk of some individual components
of metabolic syndrome. But the current study is the first to show an
association with the collection of risk factors, according to the researchers,
led by Dr. Inkyung Baik of
They found that of 232 men who said they ate fish every day at the study's outset, 29 -- or about 12 percent -- developed metabolic syndrome over the next three years. Of the 190 men who said they ate fish less than weekly, 16 percent developed metabolic syndrome.
When Baik's team considered other factors -- including the men's income and education, body weight and lifestyle habits such as smoking and exercise -- daily fish consumption was linked to a 57 percent lower risk of metabolic syndrome versus less-than-weekly consumption.
There was no such association seen among women, however.
The reason for the gender discrepancy is not clear. The researchers speculate that, as a group, women may not have gotten enough omega-3 fatty acids from fish to show a reduction in the risk of metabolic syndrome.
Men in the top 10 percent for omega-3 intake from fish typically got 786 milligrams (mg) per day, while their female counterparts got 563 mg.
Men in that top omega-3 group also showed a lower risk of metabolic syndrome than those in the bottom 10 percent -- which, according to Baik's team, supports the theory that it is the fats that explain the connection between fish and the risk of metabolic syndrome.
However, this type of study cannot by itself prove cause-and-effect.
findings need to be confirmed by other investigators," Dr. Chol Shin, one
of the researchers on the study and a professor at
And in general, it is not yet clear what the optimal daily intake of omega-3 fatty acids might be, Shin noted.
However, she adds, the American Dietetic Association and other groups have suggested a daily allowance of anywhere from 250 to 500 mg of EPA and DHA, based on the overall body of research into omega-3s and .
Two servings of fatty fish per week would be enough to achieve those levels, Vannice notes.
That also fits in with the current advice from the American Heart Association that adults strive to eat two servings of fish, preferably fatty varieties, each week.
However, even if eating fish regularly does help reduce the risk of metabolic syndrome or its components, it would be only one of many factors involved. A healthy weight, not smoking, regular exercise, and a balanced diet rich in fruits, vegetables, high-fiber foods and "good" unsaturated fats are all considered important.
current study was funded by
Journal of the American Dietetic Association, July 2010.
Thursday, July 22, 2010
ScienceDaily (July 22, 2010) — Children with celiac disease need
to include certain must-have vitamins in their diets to stave off weak bones
and osteoporosis, say researchers at the
A study of 43 children and teens from three to 18 years of age diagnosed with celiac disease showed that they also tended to have low bone density, likely due to poor intake and absorption of vitamins and minerals. That means they should be getting more of bone-boosting vitamins such as K and D in their diets, says Diana Mager, a professor of agricultural, food and nutritional science at the U of A, and one of the researchers on the project.
"Children with celiac disease are at risk for poor bone health, but by adding vitamins K and D to their diets, it can help reduce the risk of fractures and osteoporosis," Mager said.
The study revealed that the children were getting less than 50 per cent of their recommended dietary intake of Vitamin K, and that they also suffered from low levels of Vitamin D, which can be raised through increased exposure to sunlight and by eating fortified dairy products.
Mager also recommends that children with celiac disease include physical activity in their daily routines to build their bone strength and boost their Vitamin D intake by exercising outside.
"Enjoying activities such as walking and running outdoors when there is more sunshine is a great way to contribute to healthy bones," Mager said.
Wednesday, July 21, 2010
Wednesday, July 21, 2010
ScienceDaily (July 20, 2010) — A combination of nutrients called NT-020 promoted adult neural stem cell proliferation in aged rats and boosted their memory performance, reported University of South Florida researchers studying natural therapeutic approaches to promoting the health of neurons in the aging brain.
Researchers from the USF Department of Neurosurgery and Brain Repair tested two groups of aged laboratory rats; one group received NT-020 and another, the control group, did not. In the NT-020 group, the process by which neurons are generated -- called neurogenesis -- increased.
The study was published in the current issue of Rejuvenation Research (Vol. 13 No. 5, June, 2010). The NT-020 formula was patented by USF and licensed to Natura Therapeutics, Inc.
"Aging has been linked to oxidative stress, and we have previously shown that natural compounds made from blueberries, green tea, and amino acids, such as carnosine, are high in antioxidants and have anti-inflammatory and anti-oxidative activity," said Sandra Acosta, MS, the study's lead author and a PhD student in the USF Center of Excellence in Aging and Brain Repair . "The combination of these nutrients, called NT-020, creates a synergistic effect that promotes the proliferation of stem cells in the aged animals."
Acosta and colleagues compared the NT-020 group to the control group by evaluating their performance on a variety of behavioral and memory tests, including a spatial navigation test. The NT-020 group demonstrated increased adult neural stem cell proliferation in the two main stem cell niches in the brains and improvement in learning and memory.
In past studies, NT-020 has been shown to have beneficial effects on animals with simulated stroke. NT-020 has also been shown to encourage the proliferation of adult stem cells, which have the potential to develop into tissue and bone cells and also migrate to areas of damage to help with repair.
That increased stem cell proliferation coincided with better cognitive performance is significant.
"The notion that aging is a stem cell disease has been gaining popularity," said study senior author Paula Bickford, PhD, professor of neurosurgery and brain repair at USF and a senior research career scientist at the James A. Haley Veterans' Hospital (Tampa). "Our hypothesis is that aging alters the local environment in the brain and other organs and can promote an environment that retards the growth of stem cells. For example, high glucose, which would be seen with diabetes, excessive alcohol and oxidative stress, can lead to reduced neurogenesis."
The researchers concluded that increased inflammation in the brains of the aged animals led to reduced production of stem cells, but that stem cell renewal created a rejuvenating effect. They found that NT-020 treated animals had fewer activated inflammatory cells in the brain, reflecting a decrease in factors that reduced the production of stem cells.
"NT-020 may have not only a positive effect on the stem cell niche," concluded Bickford. "NT-020 may have far-reaching effects on organ function beyond the replacement of injured cells, as demonstrated by cognitive improvement in the NT-020 group."
Disclaimer statement: Paula Bickford and Paul Sanberg are co-founders of Natura Therapeutics, Inc.
S. Acosta, J. Jernberg, C.D. Sanberg, P.R. Sanberg, Brent J. Small, Carmelina Gemma, Paula C. Bickford. NT-020, a Natural Therapeutic Approach to Optimize Spatial Memory Performance and Increase Neural Progenitor Cell Proliferation and Decrease Inflammation in the Aged Rat. Rejuvenation Research, 2010; 100629131832013 DOI: 10.1089/rej.2009.1011
By Rachael Myers Lowe
Wednesday, July 21, 2010
"We all need to eat and we all encounter many food-related cues in our everyday lives," Ferriday told Reuters Health.
Ferriday enrolled 52 normal weight and 52 overweight women in the study, exposed them to the sight and smell of pizza and measured how much they salivated, as well as their psychological responses.
While lean participants didn't salivate much more once they saw and smelled the pizza, the overweight participants salivated about a third more than usual once the pizza showed up. They also had more desire to eat, measured by a standard scale, than the lean study subjects.
However, the overweight participants didn't eat more, even after being told to eat as much as they'd like.
What that means, say the researchers, is that the overweight don't necessarily eat more when at the table, but, because of their heightened sensitivity to the cues, they may be called to the table more often.
"This is potentially important, because this sensitivity may encourage snacking" and other bad that are "associated with increased energy intake, overweight and weight gain," the investigators write in the July issue of the International Journal of Obesity.
The study couldn't answer why overweight people are more turned on by food. It is not clear, for example, whether they are born that way or do eating habits learned and developed over time cause a change?
While all the subjects in this study were women, "we suspect that the findings would apply to men too," Ferriday noted.
Wednesday, July 21, 2010
(HealthDay News) -- Arthritis, the medical term for joint inflammation, commonly affects the relatively small joints of the hands.
Wednesday, July 21, 2010
The findings, published on Thursday in the journal Science Translational Medicine, may lead to a more targeted cure instead of what sufferers practice now -- life-long abstinence from food containing gluten, such as cereal, pasta, cookies and beer.
"If you can (narrow down) the toxicity of an allergen to a few components, that enables you to make a highly targeted therapy in a way that you no longer need to target the whole immune system," said researcher Robert Anderson of The Walter and Eliza Hall Institute of Medical Research in Victoria, Australia.
The sufferer is subject to chronic fatigue and risks osteoporosis, infertility, miscarriage and even cancers of the digestive tract -- symptoms of what is called celiac disease.
gluten has some 16,000 components,
"To our surprise, the majority of the immune response to gluten can fall back to just three components of gluten. It means the immune response is highly focused on maybe some particular forbidden fragments of the gluten," he said by telephone.
Anderson and some colleagues had since gone on to design an injectable drug containing very small doses of each of the three components.
The idea is to expose the immune system to regular but very small doses of the offending allergens so that the body can gradually get used to them.
(Reporting by Tan Ee Lyn; Editing by Ken Wills and Ron Popeski)
Wednesday, July 21, 2010
In an analysis of a dozen studies on coffee intake and prostate cancer risk, researchers found no strong evidence linking the beverage to either an increased or decreased risk of the disease.
A number of studies have found connections between regular coffee consumption and certain cancers -- a decreased risk in some cases, and an increased risk in others. A study published last month, for example, found that coffee drinkers had a lower risk of head and neck cancers than non-drinkers did, with the risk declining as coffee consumption rose.
Studies on prostate cancer have come to conflicting conclusions, with some linking greater coffee consumption to a heightened risk of the cancer and others showing no relationship between the two.
Overall, they found no strong relationship between men's reported coffee-drinking habits and their risk of prostate cancer.
According to the researchers, the discrepancies among past studies on coffee and prostate cancer risk may be explained by the studies' designs.
Of the studies the researchers reviewed, eight were what are known as case-control studies, where people with a disease are compared with similar individuals -- typically of the same age and sex -- who are free of the disease.
Those types of studies have a number of limitations, including the fact that participants are asked to recall their past lifestyle habits.
So, for example, because is often seen as a less-than- healthy habit, prostate cancer patients may recall their consumption as being greater than it actually was. Healthy study participants, on the other hand, may have an overly rosy view of their lifestyle habits.
When Park's team looked only at the case-control studies, there was an association between greater coffee intake and higher prostate cancer risk. However, the same was not true of the remaining four studies, which were what are known as cohort studies.
In those studies, men initially free of prostate cancer were asked about their coffee-drinking habits, then followed over time to see which ones developed prostate cancer. That type of study produces stronger evidence of a link, or lack thereof, between an "exposure" -- in this case, coffee intake -- and a than a case-control study can.
Because the cohort studies in this review showed no connection between coffee and prostate cancer, Park's team concludes that "there is no evidence to support a harmful effect of coffee consumption on prostate cancer risk."
Still, it is plausible, based on , that coffee could have both positive and negative effects on the risks of some cancers, Park's team points out. Animal research suggests, for example, that caffeine can either suppress or stimulate tumors, depending on which animal species is studied and the point in the cancer process at which the caffeine is administered.
In addition to caffeine, coffee contains more than one thousand chemicals, some of which appear to have antioxidant effects that could help protect cells from damage that can lead to cancer.
However, exactly how all those chemicals interact in the human body, and whether coffee has real effects on the risks of various cancers, remains unclear.
BJU International, online June 30, 2010.
Tuesday, July 20, 2010
Tuesday, July 20, 2010
ScienceDaily (July 20, 2010) — Regularly using a mobile phone for at least four years seems to be associated with a doubling in the risk of developing chronic tinnitus (persistent ringing/roaring/hissing in the ear), indicates a small study published online in Occupational and Environmental Medicine.
The prevalence of chronic tinnitus is increasing, and is currently around 10 to 15% in the developed world, say the authors. There are currently few treatment options.
And while there are some obvious triggers, such as ear disorders and head trauma, there are few known risk factors or clear explanations for this trend. The high microwave energy produced by mobile phones during use has been suggested as a possible culprit, but there has been no hard evidence to date.
The authors compared 100 patients who required treatment for chronic tinnitus, defined as lasting at least three months, with 100 randomly selected people without the disorder, but matched for age and sex, over a period of a year (2003-4).
Any patient with ear disease, noise induced impaired hearing, high blood pressure, or who was on medication known to boost the risk of tinnitus was excluded from the study.
All participants were then quizzed about the type of phone they used, and where, as mobile phone output tends to be stronger in rural areas. They were also asked about the intensity and duration of calls, ear preference, and use of hand held devices.
Most tinnitus was one sided, with the left side accounting for 38 cases. A similar number of patients described it as distressing 'most of the time.' More than one in four (29%) also had associated vertigo.
Virtually all the participants were mobile users, but only 84 patients and 78 in the comparison group were using a mobile when symptoms first appeared. Some 17 patients and 12 of their peers had been using a mobile for less than a year at that time.
Analysis of the results showed that the patients who had used a mobile before the onset of tinnitus were 37% more likely to have the condition than those in the comparison group. Those who used their mobiles for an average of 10 minutes a day were 71% more likely to have the condition.
Most people used their phones on both ears, and those who had used a mobile for four years or more were twice as likely to have tinnitus compared with those in the comparison group.
The authors accept that people are likely to over/underestimate their mobile phone usage and the length of calls. But they caution: "Considering all potential biases and confounders, it is unlikely that the increased risk of tinnitus from prolonged mobile phone use obtained in this study is spurious."
They suggest that there is a plausible explanation for a potential link between mobile phones and tinnitus as the cochlea and the auditory pathway directly absorb a considerable amount of energy emitted by a mobile.
H.-P. Hutter, H. Moshammer, P. Wallner, M. Cartellieri, D.-M. Denk-Linnert, M. Katzinger, K. Ehrenberger, M. Kundi. Tinnitus and mobile phone use. Occupational and Environmental Medicine, 2010; DOI: 10.1136/oem.2009.048116
Tuesday, July 20, 2010
Researchers analyzed nearly 3,000 cases of bladder cancer in professional painters that were reported in 41 previous studies. Some of those studies also classified plasterers, glaziers, wallpaper hangers, artists and decorators as painters.
While there was some evidence that female painters were more likely to develop bladder cancer than male painters, only four of the studies included separate results for women.
The number of years a person worked as a painter had a significant effect on bladder cancer risk. People who worked as a painter for more than 10 years were more likely to develop the disease than those who'd been painters for less than 10 years, according to the report published online July 20 in Occupational and .
It's not known which chemicals in paint increase the risk of bladder cancer and the link between being a painter and bladder cancer is complicated by work variability, differing levels of exposure and changes to the composition of paint over time, the researchers noted. Painters are exposed to some of the same chemicals that are found in cigarette smoke, including aromatic amines, they added.
"Because several million people are employed as painters worldwide, even a modest increase in the relative risk is remarkable," the researchers wrote in their report.
The has more about bladder cancer.
Tuesday, July 20, 2010
ScienceDaily (July 20, 2010) — Men who had a history of asthma or eczema generally had a lower risk of developing cancer, according to a study carried out by researchers at INRS-Institut Armand-Frappier, the Research Centre of the Centre hospitalier de l'Université de Montréal, and McGill University. The findings, published in the Annals of Allergy, Asthma & Immunology, show that male eczema sufferers had a lower risk of lung cancer while those with a history of asthma had a similar effect in relation to stomach cancer.
"Asthma and eczema are allergies brought about by a hyper-reactive immune system -- a state which might have enabled abnormal cells to have been eliminated more efficiently, thereby reducing the risk of cancer," explained Professor Marie-Claude Rousseau of the INRS-Institut Armand-Frappier, one of the co-authors of the research.
The researchers analyzed information that was collected
in a study on exposures in the workplace and the risk of developing cancer,
undertaken between August 1979 and March 1986. It involved 3,300 men, between
35 and 70 years of age, who had been diagnosed with cancer in one of
These findings contribute important knowledge to population health and provide new research leads. Although the study did not allow to identify which specific factors related to asthma and eczema were responsible for reducing the risk of cancer, it offers new angles for research into the molecular and immunological mechanisms that are involved in immunostimulation, a potentially promising strategy for cancer prevention.
The epidemiological study was undertaken by Mariam
El-Zein, Marie-Élise Parent, Yves St-Pierre and Marie-Claude Rousseau of the
INRS; Khady Kâ of McGill University, and Jack Siemiatycki of the Research
Centre of the Centre hospitalier de l'Université de Montréal and of Université
de Montréal. It received funding from Health
et al. History of asthma or eczema and
cancer risk among men: a population-based case-control study in
By Anne Harding
Tuesday, July 20, 2010
And while it's not clear why from the current study, the study does provide an important take home message, according to Dr. Robert S. Kirsner of the University of Miami Miller School of Medicine: "Just because you have darker skin pigmentation, whether you're Hispanic or black, does not make you immune to ," he told Reuters Health.
Melanoma remains much rarer among blacks and Hispanics than among whites, which helps explain why public health efforts to prevent melanoma chiefly target the light-skinned among us.
In the current study, for example, in 2004 there were about 26 cases of melanoma diagnosed for every 100,000 persons per year among US whites, compared to 4 cases for Hispanics and less than 1 case for non-Hispanic blacks.
Nevertheless, non-whites with melanoma are diagnosed later, and are thus actually more likely to die from the disease, Kirsner and his team point out in the Archives of Dermatology.
"It's picked up later and a lot of this is really felt to be due to decreased detection and screening," Dr. Melody Eide, a staff physician-scientist at in Detroit who has studied ethnicity and melanoma but was not involved in the new study, told Reuters Health.
determine whether trends in melanoma incidence in
showed that Hispanic men living in
Lumping all Hispanics into a single category when studying melanoma incidence is problematic, Kirsner noted. "Not all Hispanic people are from the same country, and they don't have the same skin type," he said.
There needs to be better awareness among non-white patients -- and their doctors -- that dark skin doesn't confer immunity to melanoma, according to Kirsner. People of any color should watch for skin growths that meet any of these criteria, he added: asymmetrical; irregular, nicked or notched borders; multiple colors; the or larger; or growths that are evolving or changing.
"If you have one it doesn't mean you have melanoma, but it does mean perhaps that you should have it evaluated to make sure that nothing's going on," Kirsner said.
And regardless of whether you have light or dark skin, Kirsner said it's best to follow "sun-smart" behaviors like seeking out shade, covering up, avoiding the midday sun, and wearing sunscreen.
"It's really important that people know that regardless of their skin color there is a risk of melanoma," Eide agreed.
Archives of Dermatology, July 2010.
Tuesday, July 20, 2010
ScienceDaily (July 20, 2010) — A new study led by a team of Boston University School of Public Health researchers suggests a link between polyfluoroalkyl chemicals (PFCs), industrial compounds which are widely used in many consumer products, and attention deficit hyperactivity disorder (ADHD) in children.
Published online, ahead of print, in the journal Environmental Health Perspectives, the researchers found "increased odds of ADHD in children with higher serum PFC levels." The researchers used data from the National Health and Nutrition Examination Survey (NHANES) to compare the PFC levels found in serum samples taken from 571 children, ages 12 to 15. The parents of 48 of these children reported their children were diagnosed with ADHD, one of the most common neurodevelopmental disorders in children.
NHANES is an ongoing national survey of a representative
sample of the
PFCs are highly stable compounds used in industrial and
commercial products like stain-resistance coatings, food packaging, and
fire-fighting foams. In a 2003-2004 survey, NHANES examined 2,094 blood samples
taken from the
Although the study indicates there is a link between PFCs and ADHD, lead author Kate Hoffman said it is not known if there is a causal relationship between the two.
"There's a link between this exposure and outcome but we're not really sure what way that goes," said Hoffman, PhD, who conducted the study while completing her doctorate in environmental health at BUSPH. "What we can say is children with this outcome tend to have higher levels of PFCs in their blood." Because the PFC measurements were collected at the same time as the parental report of ADHD diagnosis, Hoffman said it is unknown whether children with ADHD engage in behavior leading to increased PFC exposure or if higher serum PFC levels in children result in ADHD.
The researchers examined the connection between four PFCs, perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS) and samples from children in which there were parental reports of ADHD diagnosis.
The authors focused on ADHD because studies on animals have suggested exposure to PFCs can have neurotoxic effects. There is little information, however, on the chemicals' effects on human development.
ADHD is one of the most common neurodevelopmental disorders, Hoffman said. It is also unknown what causes ADHD, she said, but genetic and environmental factors have been associated with the disorder.
"Given the extremely prevalent exposure to PFCs, further investigation into the impact of PFC exposure on ADHD and other neurodevelopmental endpoints is warranted," the authors wrote.
Co-authors of the article include Boston University
School of Public Health faculty members Thomas Webster, DSc, associate
professor of environmental health; Janice Weinberg, ScD, associate professor of
Hoffman, Thomas F. Webster, Marc G. Weisskopf, Janice Weinberg, Verónica M.
Vieira. Exposure to Polyfluoroalkyl
Chemicals and Attention Deficit Hyperactivity Disorder in
Tuesday, July 20, 2010
Tuesday, July 20, 2010
ScienceDaily (July 20, 2010) — Among persons with psoriasis, those who reported being obese at age 18 had an increased risk of developing psoriatic arthritis, according to a report in the July 19 issue of Archives of Dermatology, one of the JAMA/Archives journals.
Psoriatic arthritis is a specific type of arthritis that develops in the joints of some patients who have psoriasis. According to background information in the article, "obesity has emerged as a significant risk factor for psoriasis," and "psoriatic arthritis affects 6 percent to 42 percent of people with psoriasis." Additionally, "psoriatic arthritis shares some clinical features with rheumatoid arthritis, both leading to joint destruction and significant morbidity."
Razieh Soltani-Arabshahi, M.D., of the University of Utah
School of Medicine,
The study found that body mass index (BMI) at age 18 was predictive of psoriatic arthritis. Other predictors included younger age at psoriasis onset, being female and having larger body surface areas affected with psoriasis. Additionally, the findings show "the obese group having an earlier onset of psoriatic arthritis, followed by the overweight group and finally the normal BMI group." Twenty percent of the overweight or obese group developed psoriatic arthritis by age 35 years while 20 percent of those individuals in the normal BMI group developed psoriatic arthritis by age 48.
The authors conclude that their findings, "support a growing concept that patients more prone to psoriatic arthritis might benefit from more frequent and meticulous screening measures for early detection and treatment of psoriatic arthritis, i.e., before the development of irreversible joint destruction."
Editorial: Identification of Risk Factors for Psoriatic Arthritis
"In most patients with psoriatic arthritis, the
symptoms do not develop until years after the onset of cutaneous
psoriasis," write Alexis Ogdie, M.D., and Joel M. Gelfand, M.D., M.S.C.E,
of the University of Pennsylvania Hospital,
"With the exception of severity of skin psoriasis, the existing studies of risk factors for psoriatic arthritis have yielded generally inconsistent findings," the authors write. Additionally, "epidemiologic studies evaluating risk factors for psoriatic disease did not start until very recently, and very few environmental risk factors (such as obesity and smoking for psoriasis) have been identified and confirmed in more than one study."
"Using data accrued in the coming years, future risk factor studies might overcome the methodologic challenges of previous investigations, and we eagerly await the results. Ultimately, identification of risk factors for psoriatic arthritis holds the promise of improving our ability to diagnose this condition and prevent it through risk-factor modification."
Razieh Soltani-Arabshahi; Bob Wong; Bing-Jian Feng; David E. Goldgar; Kristina Callis Duffin; Gerald G. Krueger. Obesity in Early Adulthood as a Risk Factor for Psoriatic Arthritis. Arch Dermatol, 2010; 146 (7): 721-726 [link]
Ogdie; Joel M. Gelfand. Identification
of Risk Factors for Psoriatic Arthritis: Scientific
Tuesday, July 20, 2010
Anne-Claire Vergnaud of Imperial College London in the
The study included more than 100,000 men and 270,000 women from 10 different European countries participating in a study of cancer and nutrition and other lifestyle factors.
Danes, Germans, Spaniards and Swedes were the biggest meat-eaters, with men eating around 300 calories worth of meat daily and women consuming 200 calories. Among all meat-eating populations, Greeks ate the least (about 200 calories a day for men and 140 for women).
Over the 5-year follow-up period, both men and women gained about a pound a year, on average, although women gained a little less. And the more meat a person ate, the more they gained; for every additional 250 grams of meat a person ate daily (the equivalent of a half-pound, 450-calorie steak), their 5-year would be 4.4 pounds greater, the researchers calculate.
When the researchers looked at different types of meat separately, they found the strongest association with weight gain for poultry, followed by processed meats and red meat.
Heavy meat-eating could be part of an overall unhealthy diet or unhealthy lifestyle, Vergnaud and her team note.
Because meat is "energy-dense" (meaning it packs more calories by weight than veggies or fruits, for example), it could influence , they add. However, the researchers did attempt to take overall dietary pattern into account, as well as education, physical activity level, whether or not people smoked, and their .
Based on the findings, a person who cut their meat consumption by 250 grams daily (about a half-pound) could conceivably reduce their 5-year weight gain by around 4 pounds.
While this is a relatively small amount of weight from an individual's point of view, the researchers add, gaining an average of 4 pounds in 5 years "could have an important effect from a population perspective."
"More importantly," they add, "our results do not support that a high-protein diet prevents obesity or promotes long-term weight loss, contrary to what has been advocated."
Monday, July 19, 2010
By Serena Gordon
Monday, July 19, 2010
MONDAY, July 19 (HealthDay News) -- To try and lessen the effects of the common cold, many people have turned to homeopathic remedies, including products containing zinc.
However, a new analysis suggests that nasal gels containing zinc and nasal swabs with zinc have most likely caused a loss of smell in some users.
my practice, we started seeing people using the zinc nasal gel. They squirted
it in, took a deep sniff and then had an incredibly intense burning sensation
that lasted for several hours. When these people recovered, they found they had
no sense of smell," explained study author Dr. Terence Davidson, director
The loss of smell is called anosmia, and Davidson said that people might not appreciate how significant it can be. "Most of us take our sense of smell for granted. But, people need to take a moment to realize how important smell is. It helps us avoid dangers when we smell smoke or gas or rotten, spoiled food and it brings us incredible pleasure -- think about the smell of our homes, loved ones, food, coffee. In fact, 90 percent of our appreciation for food comes from our sense of smell," he said.
Davidson said that some of the people affected by the zinc-induced anosmia filed lawsuits against the manufacturers of these products. However, there are no randomized, controlled clinical trials that conclude a loss of smell is one of the possible outcomes from using these products, making it harder to prove cause-and-effect.
Since it would be impossible, as well as unethical, to try to conduct such a study now, Davidson and his colleague, Dr. Wendy Smith, applied the "Bradford Hill Criteria" to 25 patients they had seen for the sudden loss of smell after using a zinc gel product.
The Bradford Hill Criteria were developed in 1965 by a statistician who wanted to establish a causal link between tobacco smoking and lung cancer. The nine key criteria necessary to find a causal link include: strength of the association, consistency, specificity, timing, dose-response (does more of the substance make the problem worse?), biological plausibility, biological coherence, experimental evidence and analogy.
"Dr. Smith and I applied the criteria to zinc-induced anosmia and conclusively show that nasal zinc was the cause of the subsequent loss of smell," said Davidson.
The finding is published in the July issue of the Archives of Otolaryngology, Head and Neck Surgery.
In addition, the efficacy of these products in reducing cold symptoms is "questionable," according to the study.
The patients seen by the researchers had a permanent loss of smell, but Davidson said there are likely people who have had lesser degrees of damage from these products as well.
Homeopathic remedies like nasal zinc aren't subject to the same rules and regulations that prescription and over-the-counter medications are. However, in June 2009, the U.S. Food and Drug Administration recommended that consumers stop using these products and requested that the manufacturers stop selling them, which they did. Oral zinc products are not associated with this problem and remain on the market.
HealthDay was unable to reach a spokesperson for Matrixx Initiatives, a former manufacturer of nasal zinc. However, in a press release dated June 16, 2009, William J. Hemelt, acting president of Matrixx Initiatives, said, "It is well-understood in the medical and scientific communities that the most common cause of anosmia is the common cold, which Zicam Cold Remedy intranasal gel products are taken to treat." He said that, "given the enormous number of doses sold and colds treated," there's no cause to think that the number of cases of anosmia reported is any more than what might be expected in the general population. "There is no reliable scientific evidence that Zicam causes anosmia," Hemelt concluded.
But another expert isn't so sure.
think this study was well-done, and I think intranasal zinc can impair the sense
of smell. Does it happen all the time? No. Is it a rare event? No," said
Dr. Marc Siegel, an associate professor of medicine at the New York University
School of Medicine and the
The take-home message for consumers, said Davidson, is to "be careful about the things you put into your body. Whether it's a drug or a homeopathic medicine, not all are safe, so be careful."
Learn more about nasal zinc products and the loss of smell from the U.S. Food and Drug Administration.
Monday, July 19, 2010
ScienceDaily (July 19, 2010) — Consuming higher amounts of omega-3 fatty acids does not appear to lower heart disease risk for women with type 1 diabetes, according to a University of Pittsburgh Graduate School of Public Health study being presented at the 70th Scientific Sessions of the American Diabetes Association.
The study included 601 men and women enrolled in the Pittsburgh Epidemiology of Diabetes Complications Study, a long-term prospective examination of childhood onset type 1 diabetes that began in 1986. Participants were diagnosed with type 1 diabetes between 1950 and 1980.
Omega-3 fatty acids, primarily found in fish, promote heart health by preventing the buildup of cholesterol in the arteries. Little is known about the effect of consuming omega-3 in people with type 1 diabetes, who are at much greater risk for heart disease.
During the course of the study, 166 participants (27.6 percent) were diagnosed with cardiovascular disease. Generally, omega-3 intake among participants was low. The incidence of heart disease was lowest in men who consumed the highest quantities of omega-3 -- more than 0.2 grams per day. Women who consumed similar amounts of omega-3 did not have lower rates of heart disease.
"Although omega-3 is typically associated with decreased risk for cardiovascular disease, this may not be the case for women who have type 1 diabetes," said Tina Costacou, Ph.D., lead author of the study and assistant professor of epidemiology, University of Pittsburgh Graduate School of Public Health. "Importantly, our study suggests we shouldn't assume men and women with type 1 diabetes are the same."
Study co-authors include Cathy E. Lloyd, Ph.D., and
Trevor Orchard, M.D., of the
By Amy Norton
Monday, July 19, 2010
The findings, reported in the journal Ophthalmology, do not prove that eating fish cuts the risk of developing the advanced stages of age-related macular degeneration, or AMD.
But they add to evidence from previous studies showing that fish eaters tend to have lower rates of AMD than people who infrequently eat fish.
AMD is caused by abnormal blood vessel growth behind the retina or breakdown of light-sensitive cells within the retina itself -- both of which can cause serious vision impairment. AMD is the leading cause of blindness in older adults.
There is no cure for AMD, but certain treatments may prevent or delay serious vision loss.
fish or omega-3 supplements can stall AMD progression is not yet clear. But a
follow-up to the
the current study, Bonnielin K. Swenor and colleagues at
Fifteen percent were found to have early- or intermediate-stage AMD, while just under 3 percent were in the advanced stage of the disease.
Overall, Swenor's team found, there was no clear relationship between participants' reported fish intake and the risk of AMD. However, there was a connection between higher intake of omega-3-rich fish and the odds of advanced AMD.
Study participants who ate one or more servings of such fish each week were 60 percent less likely to have advanced AMD than those who averaged less than a serving per week.
That was with factors like sex, race and smoking habits -- which have been linked to AMD risk -- taken into account; women appear to be at greater risk of AMD than men, while whites are at greater risk than African Americans and smokers face a higher risk than non-smokers.
Still, the findings do not prove that omega-3-rich fish bestowed the benefit.
She pointed out that this study was "cross-sectional" -- meaning it assessed participants at one time point, rather than following them over time to see whether self-reported fish eaters were less likely to develop AMD. So it is not clear whether participants' reported diet habits preceded the development of the .
The study also relied on people to accurately recall and report their typical eating patterns, which is subject to error.
Nor is it clear, Swenor said, why greater consumption of omega-3-rich fish was related to a lower risk of advanced, but not earlier-stage, AMD.
For now, she suggested that people with AMD discuss all their "dietary options" with their ophthalmologist.
In general, though, eating fish regularly is considered a healthy move. The American Heart Association, for example, recommends that all adults aim to eat fish, preferably fatty varieties, at least twice per week, for the potential benefits for .
Ophthalmology, online July 13, 2010.
Monday, July 19, 2010
ScienceDaily (July 19, 2010) — Revealing the science behind the homespun advice, a team of researchers at Worcester Polytechnic Institute (WPI) has identified and measured the molecular forces that enable cranberry juice to fight off urinary tract infections in people.
The data is reported in a paper published in the journal Molecular Nutrition and Food Research. The research illuminates the basic mechanics of E. coli infections, which has implications for developing new antibiotic drugs and infection-resistant materials for invasive medical devices.
The research team led by Terri Camesano, professor of chemical engineering at WPI, focuses on the virulent form of E. coli bacteria that is the primary cause of most urinary tract infections. This strain of E. coli is covered with small hair-like projections known as fimbriae which act like hooks and latch onto cells that line the urinary tract. When enough of the virulent E. coli adhere to cells in this way, they cause an infection. Previous work by Camesano has shown that exposure to cranberry juice causes the fimbriae on E. coli to curl up, reducing their ability to attach to urinary tract cells. In the new study, Camesano's team presents the first specific measurements of the mechanical forces involved in the attachment of the virulent E. coli to human urinary tract cells. The study also documents how the force of attachment is reduced in the presence of cranberry juice cocktail. "This is not a clinical study -- it's a mechanical study that shows us the direct forces that can lead to infection," Camesano said.
To make measurements at the molecular level, Camesano's team developed a method to attach a single E. coli cell to the tip of a probe mounted on a device called an atomic force microscope (AFM). The probe was then dipped in a solution containing human uroepithelial cells, which line the urinary tract. The fimbriae on the E. coli latched onto to specific structures on the human cells, similar to the way the two halves of a Velcro fastener come together. The probe on the AFM was then pulled away from the human cells, measuring the amount of force needed to tear the E. coli away. "We know, on average, how many fimbriae are on each E. coli cell. And the total force we measured correlates with that number. So the data lead us to believe that the fimbriae each bind to a specific receptor on the uroepithelial cells," Camesano said.
The experiment was repeated numerous times with solutions containing human cells and various concentrations of commercially available cranberry juice cocktail. The data showed that the attachment force of the virulent E. coli weakened as the amount of cranberry juice cocktail increased. The study also showed that a strain of E. coli without fimbriae did not bind well to the human urinary tract cells, regardless of the concentration of cranberry juice cocktail, providing further evidence that fimbriae are essential for infection.
Furthermore, Camesano's team found that in the absence of cranberry juice, the strength of the virulent E. coli's bond to the human cells was so strong that it could not be broken by the typical force of urine flowing through a person's urinary tract. However, as the cranberry juice concentration increased, the bond weakened to the point where the E.coli could be stripped away by the force of flowing urine. "The shear force created by flowing urine is a defense mechanism against urinary tract infection," Camesano said.
Since bacterial adhesion is required for infection, Camesano said understanding the specific mechanisms and forces involved will help direct future studies aimed at identifying potential drug targets for new antibiotics. The data may also be useful in studies aimed at engineering the surfaces of invasive medical devices like catheters to make them more resistant to bacterial adhesion.
The research detailed in the current study was supported by grants from the National Science Foundation, the Cranberry Institute and the Wisconsin Cranberry Board.
Yatao Liu, Paola A. Pinzón-Arango, Amparo M. Gallardo-Moreno, Terri A. Camesano. Direct adhesion force measurements between E. coli and human uroepithelial cells in cranberry juice cocktail. Molecular Nutrition & Food Research, 2010; DOI: 10.1002/mnfr.200900535
By Frederik Joelving
Monday, July 19, 2010
The findings add to an ongoing debate over the importance of high cholesterol in children, and whether cholesterol-lowering drugs are appropriate when changes in diet and physical activity don't cut it.
The new study, published in the journal Pediatrics, shows that after a few years, some youngsters with high cholesterol would no longer be considered for drug treatment according to guidelines.
While this isn't an argument to abandon drug therapy altogether, doctors shouldn't jump the gun when treating kids for cholesterol, the researchers caution.
"Both in kids and in adults there is quite a bit of variability over time," David S. Freedman of the CDC told Reuters Health. "People with very, very high cholesterol are likely to be those that are having a bad cholesterol day."
"My paper emphasizes that you probably need at least two or three measurements to screen out kids who are just having a bad day," he added.
"The advice is very well taken," Dr. William Neal, who wasn't involved in the study, told Reuters Health.
Last week, a research team led by Neal, of West Virginia University in Morgantown, found that among fifth-graders from West Virginia, as many as one-third with at or above 160 mg/dL would not be screened under current government guidelines. That led the team to recommend screening all children, although an independent expert said the evidence doesn't support that conclusion. (See Reuters Health story of July 12, 2010, http://link.reuters.com/cen97m )
Neal said he uses statins in children who don't benefit from changing lifestyle, but he virtually never starts medication without doing two cholesterol tests spaced months apart.
"I don't think (the new study) is going to alter my practice or my beliefs much," he said.
CDC researchers examined how cholesterol levels changed over time in a group of
more than 6,800 children from
Initial levels of LDL ("bad") cholesterol turned out to be strongly linked to later levels, even after 20 years. But as time went by, the differences in cholesterol between kids tended to shrink, with very high levels slumping and low levels rising. The researchers said the changes might have had nothing to do with diet or exercise changes, although they couldn't say for sure.
The biggest drops were seen in kids who initially had very high cholesterol, landing some in a range that no longer warrants drugs, according to guidelines.
Since 2008, the has recommended that drug treatment be considered in cases where LDL cholesterol in the blood is at least 190 milligrams per deciliter (mg/dL); if a parent or grandparent has heart disease or high cholesterol, the threshold is 160 mg/dL.
After four years, cholesterol levels had fallen below that threshold 60 percent of the time in kids that initially landed above it, the new report shows.
"Although for the most part children with extremely high levels had high levels at reexamination," the researchers write, "the changes in LDL cholesterol levels that occurred between examinations would have altered the recommended dietary or pharmacologic interventions for many children."
The fundamental question, however, is what to do with those kids who have high cholesterol.
Dr. Michael L. LeFevre, of the
For that reason, the U.S. Preventive Services Task Force, a federal expert panel of which LeFevre is a member, currently doesn't recommend routine cholesterol screening in any children.
Pediatrics, online July 19, 2010.
Monday, July 19, 2010
ScienceDaily (July 19, 2010) — Research to be presented at the Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB), the foremost society for research into all aspects of eating and drinking behavior, finds that prolonged exposure to a high fat diet is correlated with changes in the brain chemical dopamine within the striatum, a critical component of the brain's reward system.
The authors measured 'real-time' changes in dopamine
levels after rats consumed a high fat diet for either 2 or 6 weeks. Compared to
rats consuming a standard low fat diet, high-fat diet rats exhibited reduced
dopamine release and also reduced reuptake by "dopamine transporters"
within the striatum. Mitchell Roitman from the
The results from this study highlight the impact of diet on brain neurochemistry -- and in particular on brain systems that regulate motivation and willingness to work for food reward in rats as well as humans.
Research supported by the National Institute on Drug Abuse (NIDA).
The lead author is Jackson J. Cone,